SWIG: Expose S2::S2PolygonLayerOptions and S2::S2Builder

src/python/pywraps2_test.py

@@ -1070,5 +1070,66 @@ def testUnionDistinct(self):
     loop = result.loop(1)
     self.assertEqual(4, loop.num_vertices())
 
+class S2BuilderTest(unittest.TestCase):
+  def setUp(self):
+    self.p1 = s2.S2LatLng.FromDegrees(10.0, 10.0).ToPoint()
+    self.p2 = s2.S2LatLng.FromDegrees(10.0, 11.0).ToPoint()
+    self.p3 = s2.S2LatLng.FromDegrees(11.0, 10.0).ToPoint()
+    self.p4 = s2.S2LatLng.FromDegrees(11.0, 11.0).ToPoint()
+
+  def testSquareDirected(self):
+    opts = s2.S2PolygonLayerOptions()
+    opts.set_edge_type(s2.S2Builder.EdgeType_DIRECTED)
+
+    result = s2.S2Polygon()
+    b = s2.S2Builder()
+    b.StartLayer(s2.S2PolygonLayer(result, opts))
+
+    b.AddEdge(self.p1, self.p2)
+    b.AddEdge(self.p2, self.p4)
+    b.AddEdge(self.p4, self.p3)
+    b.AddEdge(self.p3, self.p1)
+
+    b.Build()
+
+    self.assertEqual(1, result.num_loops())
+    loop = result.loop(0)
+    self.assertEqual(4, loop.num_vertices())
+
+  def testSquareUndirected(self):
+    opts = s2.S2PolygonLayerOptions()
+    opts.set_edge_type(s2.S2Builder.EdgeType_UNDIRECTED)
+
+    result = s2.S2Polygon()
+    b = s2.S2Builder()
+    b.StartLayer(s2.S2PolygonLayer(result, opts))
+
+    b.AddEdge(self.p1, self.p2)
+    b.AddEdge(self.p1, self.p3)
+    b.AddEdge(self.p2, self.p4)
+    b.AddEdge(self.p3, self.p4)
+
+    b.Build()
+
+    self.assertEqual(1, result.num_loops())
+    loop = result.loop(0)
+    self.assertEqual(4, loop.num_vertices())
+
+  def testException(self):
+    opts = s2.S2PolygonLayerOptions()
+    opts.set_edge_type(s2.S2Builder.EdgeType_DIRECTED)
+
+    result = s2.S2Polygon()
+    b = s2.S2Builder()
+    b.StartLayer(s2.S2PolygonLayer(result, opts))
+
+    b.AddEdge(self.p1, self.p2)
+    b.AddEdge(self.p1, self.p3)
+    b.AddEdge(self.p2, self.p4)
+    b.AddEdge(self.p3, self.p4)
+
+    with self.assertRaises(ValueError):
+      b.Build()
+
 if __name__ == "__main__":
   unittest.main()

src/python/s2_common.i

@@ -48,6 +48,17 @@ public:
   }
 };
 
+// Wrapper for S2PolygonLayer::Options to work around the inability to
+// handle nested classes in SWIG.
+class S2PolygonLayerOptions {
+public:
+  s2builderutil::S2PolygonLayer::Options opts;
+
+  void set_edge_type(S2Builder::EdgeType edge_type) {
+    opts.set_edge_type(edge_type);
+  }
+};
+
 %}
 
 %inline %{
@@ -280,6 +291,19 @@ class S2Point {
   }
 }
 
+%extend S2Builder {
+ public:
+  void StartLayer(S2Builder::Layer* layer_disown) {
+    $self->StartLayer(std::unique_ptr<S2Builder::Layer>(layer_disown));
+  }
+}
+
+class S2PolygonLayerOptions {
+public:
+  s2builderutil::S2PolygonLayer::Options opts;
+  void set_edge_type(S2Builder::EdgeType);
+};
+
 // S2PolygonLayer's constructor takes a pointer to an S2Polygon. We
 // need to ensure that the S2Polygon is not destroyed while the
 // S2PolygonLayer still references it. To do this, save a reference to
@@ -288,6 +312,14 @@ class S2Point {
   self._incref = args[0]
 %}
 
+%extend s2builderutil::S2PolygonLayer {
+ public:
+  S2PolygonLayer(S2Polygon* layer,
+                 const S2PolygonLayerOptions& options) {
+   return new s2builderutil::S2PolygonLayer(layer, options.opts);
+  }
+}
+
 %extend MutableS2ShapeIndex {
  public:
   void Add(S2Polygon* polygon_disown) {
@@ -527,6 +559,13 @@ public:
 %unignore S2BufferOperationOptions::set_error_fraction;
 %unignore S2Builder;
 %unignore S2Builder::Layer;
+%unignore S2Builder::S2Builder;
+%unignore S2Builder::StartLayer(S2Builder::Layer*);
+%unignore S2Builder::AddEdge;
+%unignore S2Builder::Build;
+%unignore S2Builder::EdgeType;
+%unignore S2Builder::EdgeType::DIRECTED;
+%unignore S2Builder::EdgeType::UNDIRECTED;
 %unignore s2builderutil;
 %unignore s2builderutil::S2PolygonLayer;
 %unignore s2builderutil::S2PolygonLayer::S2PolygonLayer(S2Polygon*);